


The Presenting of Sam Winchester

by SammysGirl666



Category: Supernatural
Genre: Alpha!Dean, Alpha/Beta/Omega Dynamics, M/M, omega!Sam
Language: English
Status: Completed
Published: 2015-03-04
Updated: 2015-03-04
Packaged: 2018-03-16 08:50:13
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 1,765
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/3482003
Author URL: https://archiveofourown.org/users/SammysGirl666/pseuds/SammysGirl666
Summary: <blockquote class="userstuff">
              <p>In which Sam's biology picks a bad time to kick in and Dean has to come save the day.</p>
            </blockquote>





	The Presenting of Sam Winchester

**Author's Note:**

> This is what happens when I get bored.

When Sam spikes a fever, Dean decides to take the hunt alone. He tells Sam to relax, to stay put and rest and that they’ll leave when he gets back. Sam listens well enough because he thinks he’s sick too and the hunt is only a spirit which he knows Dean can handle. So he stays at the motel and relaxes, drinks a lot of water, and sleeps.

It’s all pretty bland until the morning of the third day that Dean is gone.

He’s sitting on the bed, eating a small breakfast when, suddenly, his insides twist up and spikes of pleasure skitter up and down his spine. His cock swells to full hardness in his sweatpants and he feels his asshole start to leak with wetness.

Shit.

He’s an omega.

Up until this point, he’d assumed he was a beta. He hadn’t shown any signs of being alpha or omega during his presenting years. He’s a late bloomer. It’s more common with omegas, especially male ones. It takes a while for the male anatomy to accommodate what it means to be an omega. So, while he’s not surprised on a scientific level, he is surprised on a “shit, did I just start leaking from my asshole?” level.

For a second, he’s so surprised, he has no idea what to do. He just sits there, mouth hanging open as sweat coats his forehead and his body becomes a needy, hot livewire, ready for an alpha’s touch.

That’s when his hunter senses kick and he realizes what kind of danger he’s in. He’s an unmated omega in heat and the only alpha that can take care of him is two towns over. He could call Castiel but that’s iffy. Cas is an unmated alpha as well, presented while he was human and everything. If he calls Cas, it could turn ugly. Alpha instincts are dangerous and can take over in the presence of omegas.

The same thing could happen with Dean. But Sam doesn’t really mind the idea of Dean claiming him and that’s a thought he should probably psychoanalyze later but, for now, he needs to make sure that no one can get into the room.

If any unsuspecting alpha were to walk by and smell his unmated scent, there’s no telling what could happen. So Sam stands up carefully, holding a hand over his stomach as he walks to the door. He just manages to get the lock in place when there’s a banging on the other side of the door.

“Hey pretty omega,” a muffled male voice says from the other side of the door, “you in there all alone?”

Sam doesn’t answer, fear hitting him hard, warring with the lust and need coursing through his veins. The pounding at the door becomes more insistent and then there’s a loud slam and another male voice comes through, then another.

Jesus, how strong does he smell, exactly?

After twenty minutes, he’s a sweaty and needy mess and there’s a horde of alphas outside his door, fighting each other and trying to get to him. It’s a crappy motel, and he’s not surprised that no staff has come to break the alphas up. Lucky for Sam, they’re too busy fighting each other to try and get into the room. The omega in him is tempted to open the door. The alpha smell is pleasing and it calls to him. However, he has the presence of mind to not go near the door. He stays on the bed and grabs a gun from under his pillow. All the while, his cock screams for attention and the slick mess between his legs gets worse.

The gun is a moot point. He couldn’t fire it even if he needed to. His heat is quickly taking over his senses and, pretty soon, he’ll be nothing but a writhing mess of want and need. The alphas on the other side of the door say lewd and violent things and Sam struggles not to obey their commands and let them in. It’s getting harder and harder for him to remain clear headed and he’s about to make a last ditch effort and call Cas when he hears two loud gunshots ring out, outside.

Sam stops breathing and his eyes snap toward the door. Did one of those alphas have a gun? Did someone just get murdered outside of his bedroom door? There’s shuffling outside, some muffled argument between two alphas and then the lock clicks. Sam scrambles up the bed, trying not to lose himself to his desire as he shakily tries to undo the safety on the gun. The door opens and Sam points the gun, safety still on, hoping against everything that the alpha that comes through the door knows nothing about guns.

“Safety’s on,” Dean says as he walks in, barely glancing at the gun before his jacket and boots are off and he’s kneeling in front of Sam on the bed.

“Did you kill those guys?” Sam asks in horror.

“No, just fired a few warning shots,” Dean says, shrugging it off. His eyes are raking over Sam and the younger man shivers. Dean smells divine, like cinnamon and pine and honey. “Shit, little brother, you really had those guys riled up though, didn’t you? You smell delicious, baby boy.”

Sam’s breath hitches when Dean noses at his throat, inhaling deeply.

“Y-you’re not surprised that I’m an omega?” Sam asks, as he feels Dean’s hands sneak under his shirt.

“Mm,” Dean hums against his throat, “not really. I knew you’d have to be, was really disappointed when you didn’t present when you were 16.”

“You knew?” Sam gasps, eyes fluttering shut at the feeling of Dean’s hands on his skin. A large spurt of slick leaks from his hole and he bites his lip to hold back a moan.

“Yeah,” Dean confirms as he straddles Sam’s legs, “knew you’d be my mate, Sammy. Knew you had to be.”

It makes sense, in a way. Alphas have instincts about these things that omegas and betas don’t. They know when it’s going to rain and when there’s danger nearby. It’s what makes Dean a good hunter.

“Yeah Dean,” Sam groans, “’m your mate.”

Dean smiles and dips his head back to nose at Sam’s neck, sighing heavily.

“God, baby brother, you smell so damn good. Will you let me take care of you, Sam? Want me knot you? Breed you? Claim you?” Dean’s voice, drops low and gravelly and right to Sam’s cock.

“Yes,” Sam gasps, “yes, god Dean, fucking do it. Fuck me.”

They shed their clothes quickly, kicking off their pants and boxers and ripping off their shirts. Sam’s sure that there should be some hesitation. Neither of them should be so eager to commit incest. But incest is a forgivable sin when it’s between an alpha/omega pair of siblings. Even then, Sam feels like this should be a bigger shift from where they were to where they’re going. But it feels natural, like they’ve been doing this all their lives and, in the end, Sam can’t really resist. He wants it. Dean wants it. Agonizing over it won’t change it.

“Wanna be my mate, Sammy?” Dean asks, as he fingers at the slick mess of Sam’s hole. Sam’s already loose and pliant, but Dean fingers him anyway. Sam’s a wreck, driving his hips down to meet the thrust of Dean’s talented digits.

“Yeah Dean,” he moans.

That’s all Dean seems to be able to handle, because in the next second he’s lining up his cock with Sam’s slick hole and pushing forward. The touch of his alpha makes Sam burn all over and he just wants more of it. He tries to force Dean’s cock the rest of the way in but Dean holds him still, pushing his hips forward slowly.

“Dean, alpha, please,” Sam whimpers, “please knot me.”

Dean groans and his hips snap forward, seemingly of their own volition, until he’s bottomed out inside of Sam. They both make pathetic sounds of need when Dean moves his hips again. Sam pulls Dean’s forward, kissing him sloppily and resting their foreheads together. Dean’s lips quirk up and he switches their position. He pulls them backward until he’s in a sitting position, leaning against the headboard, and Sam is in his lap, long legs wrapped around him. It’s not the most comfortable position for fucking but it will be good for when they’re tied.

They fuck slowly, Sam moving as Dean bounces him up and down on his cock. It gets harder and faster, as fast as they can in the position they’re in. Dean buries his face in Sam’s neck and breathes harshly, whispering little praises to Sam as the younger man falls apart on his cock.

“So fucking beautiful, Sammy,” Dean murmurs, “fuckin’ perfect for me. Gonna breed you baby, gonna make you mine.”

Sam is lost, in Dean’s words and body and they move more frantically against each other. Sam feels Dean’s knot swelling, tugging on his rim on each thrust. The knowledge that he’s being claimed by Dean, his brother, the person he’s been in love with his whole life, pushes all his buttons and it’s not long before his body is locking up and orgasm is threatening.

Sam screams when he comes, spilling over his and Dean’s stomach, shaking and sweating and begging. Dean’s knot swells to full size, locking himself to Sam and he comes, shaking. The pleasure seems endless as he spills load after load into Sam.

“Fucking Christ,” Dean whispers against Sam’s skin.

“Gonna come again, Dean,” Sam warns and then he’s moving frantically on Dean’s knot, pushing it deeper inside himself as he moves. Dean shudders and, sure enough, Sam comes again. There’s less come this time but just as much shaking and sweating and begging. Then, Sam collapses, falling forward into Dean’s arms.

“Mm,” Dean hums, “such a good boy for me, Sammy.”

“Always, Dean,” Sam mutters back.

They sit there like that for an indeterminable amount of time, as Dean’s knot slowly goes down. Sam sits in Dean’s arms, letting the older hunter pet his hair as they whisper soft words to each other.

“What if I’m pregnant?” Sam asks when Dean’s knot finally slips out of him.

“Then I’m one lucky guy,” Dean responds easily. Sam smiles, laying down next to Dean.

Whatever happens, whether Sam’s pregnant or not, he knows that it’ll be okay. Dean is his mate, his alpha and as long as that’s true, they’ll make it.

They always do.

**Author's Note:**

> find and follow me at fucktoysam.tumblr.com because I told you to.


End file.
